1. Technical Field
The present invention concerns systems useful in earth wells. This invention more specifically concerns well injection systems useful for injecting fluids in a formation encountered by an earth well bore.
2. Background Art
Various systems have been used in earth wells to pump fluids down well flow conduits for "injection" into a formation. The fluids, either liquid or gas, are usually required in larger volumes for Enhanced Oil Recovery operations, such as water, steam and CO.sub.2 injection into selected wells in a formation to "flood" the formation or reservoir to ultimately cause recovery of greater quantities of hydrocarbons from the formation than if usual recovery methods were used.
U.S. Pat. No. 4,355,686 to Henry P. Arendt and Thomas J. Heard discloses a method of operating an injection well and apparatus used in the well. This patent teaches injection through a well flow conduit into a formation after a plug is expended from the conduit, but suggests no way of controlling injected flow rates.